1. Field of The Invention
This invention generally relates to an electronic dictionary system (namely, a computerized dictionary system) and more particularly to a device (hereunder sometimes referred to as a concept dictionary management device) for managing what is called a concept dictionary in which words of an electronic dictionary are connected as networks (for instance, semantic networks) representing relationships among concepts.
2. Description of The Related Art
In recent years, there has been high interest in application of a concept dictionary management device to, for example, an expansion of a key word used for full text retrieval of information on documents.
Hereinafter, a conventional concept dictionary management system will be described. FIG. 5 is a schematic block diagram for illustrating the configuration of the conventional concept management device. In this figure, reference numeral 51 designates a fundamental concept dictionary data holding portion, or fundamental concept dictionary for holding fundamental information (hereunder sometimes referred to as fundamental concept network connection information) on connection (hereunder sometimes referred to as concept network connection, wherein a concept network connection is defined as a tree network in which a plurality of words are represented as nodes and are connected with each other on the basis of a common concept) among words connected as networks, which is used in common by a plurality of users; 52 a field concept dictionary data holding portion, or concept field of use dictionary which is used by a plurality of users in relation only to a particular field or sphere in which the fundamental concept dictionary is utilized, for holding concept network connection information (wherein concept network connection information is defined as information representing the words, as well as the connecting relations among the words, included in a concept network connection) used to add supplemental concept network connection information, which corresponds to each field or sphere employed in the concept dictionary management system, to the fundamental concept network connection information held by the fundamental concept dictionary 51; 54 a personal concept dictionary data holding portion, or personnel concept dictionary, for holding concept network connection information used by a user to personally add supplemental concept network connection information to the fundamental concept network connection information which is stored in the fundamental concept dictionary 51 and is regulated by using information held by the concept field use of dictionary 52; 56 a concept dictionary retrieval portion for retrieving concept network connection information concerned with a given word from one of the dictionaries 51, 52 and 54; 57 an operation control portion for controlling an operation of the entire concept dictionary management system.
Next, an operation of the conventional concept management system will be described hereinbelow. First, when a word (hereunder referred to as an input word) is inputted from an external device to the operation control portion 57, the operation control portion 57 issues a retrieval command to the concept dictionary retrieval portion 56 and gives the input word in order to get concept network connection information relating to this input word from the concept network connection information held in the fundamental concept dictionary 51. Then, the concept dictionary retrieval portion 56 retrieves concept network connection information relating to the given input word from the fundamental concept dictionary 51 and returns the retrieved concept network connection information to the operation control portion 57. When the operation control portion 57 receives concept network connection information from the concept dictionary retrieval portion 56, the portion 57 extracts words which are present in the received concept network connection information. Further, the portion 57 directs the concept dictionary retrieval portion 56 to retrieve concept network connection information from the field concept dictionary data holding portion, i.e., from the concept field of use dictionary 52 and gives the extracted words to the portion 56 with intention of checking expansions of concepts (namely, expansions of networks representing relationships among concepts (hereunder sometimes referred to as concept expansions)) regarding each of the extracted words according to the information held in the field concept dictionary data holding portion 52. Then, the concept dictionary retrieval portion 56 retrieves Concept network connection information held in the concept field of use dictionary 52 regarding each of the given words therefrom and returns a result of the retrieval to the operation control portion 57. When the operation control portion 57 receives the retrieved concept network connection information from the concept dictionary retrieval portion 56, the portion 57 performs what is called a "fusion" of the concept network connection information retrieved from the fundamental concept dictionary 51 and that retrieved from the concept field of use dictionary 52. Thus the portion 57 generates new concept network connection information which reflects an addition of the result of checking a concept expansion concerning each of the extracted words in the field concept dictionary data holding portion 52, i.e., the concept field of use dictionary to that of checking a corresponding concept expansion in the fundamental concept dictionary data holding portion 51, i.e., the fundamental concept dictionary. Further, the operation control portion 57 extracts words included in the new concept network connection information and directs the concept dictionary retrieval portion 56 to retrieve information from the personal concept dictionary 54 and gives the extracted words, which are extracted from the new concept network connection information, to the concept dictionary retrieval portion 56 as input words thereto, for the purpose of checking a concept expansion concerning each of the extracted words in the personal concept dictionary 54. Subsequently, the concept dictionary retrieval portion 56 retrieves concept network connection information concerning the given word from the personal concept dictionary data holding portion 54 and thereafter the portion 56 returns a result of the retrieval to the operation control portion 57. Then, the portion 57 generates further new concept network connection information by introducing the result of the retrieval from the personal concept dictionary data holding portion 54 into the concept network connection information generated as the results of the retrieval from the fundamental concept data holding portion 51 and the concept field of use dictionary 52.
Next, in order to check whether or not a further concept expansion of each of the words included in the concept network connection information added by the field concept dictionary data holding portion 52 can be detected on the basis of the information held in the fundamental concept dictionary data holding portion 51 or whether or not a further concept expansion of each of the words included in the concept network connection information added by the personal concept dictionary data holding portion 54 can be detected on the basis of the information held in the fundamental concept dictionary data holding portion 51 and that held in the field concept dictionary data holding portion 52, the operation control portion 57 extracts words from the concept network connection information concerning the input words, which is generated from the result of the retrieval from each of the concept dictionaries 51, 52 and 54. Further, the portion 57 retrieves words in the fundamental concept dictionary data holding portion 51, which are not included in the concept network connection information obtained as the result of the last retrieval from the fundamental concept dictionary 51. Then, the portion 57 modifies or corrects the concept network connection information. Moreover, the operation control portion 57 performs similar retrieval in each of the field concept dictionary data holding portion 52 and the personal concept dictionary data holding portion 54 once again. Concept network connection information concerning each of the words, which appear in the concept network connection information concerning the input words held in the operation control portion 57, is repeatedly searched for until the information held in all of the concept dictionary data holding portions dictionaries 51, 52 and 54 is searched. Upon completion of this search, resultant concept network connection information is outputted to an external device as concept network connection information concerning the input words.
Incidentally, information indicating whether or not the checking of words appearing in the concept network connection information corresponding to the input word, which information is held in each of the concept dictionary data holding portions 51, 52 and 54 is completed (namely, information indicating whether or not the searching of each of the information held in the portions 51, 52 and 54 for words appearing in the concept network connection information corresponding to the input word is completed) is represented by using a 3-bit flag consisting of three bits a, b and c which is established or set correspondingly to each word appearing in the concept network connection information when this information is processed in the operation control portion 57 as described above. Namely, in case where bit a is 1, it is indicated that the corresponding word is detected from the fundamental concept dictionary data holding portion 51 or the concept expansion to be performed on the corresponding word is completed in the fundamental concept dictionary data holding portion 51. Further, in case where bit b is 1, it is indicated that the corresponding word is detected from the field concept dictionary data holding portion 52 or the concept expansion to be performed on the corresponding word is completed in the field concept dictionary data holding portion 52. Moreover, in case where bit c is 1, it is indicated that the corresponding word is detected from the personal concept dictionary data holding portion 54 or the concept expansion to be performed on the corresponding word is completed in the personal concept dictionary data holding portion 54. Thus the concept expansion is prevented from being performed on the same word in the same concept dictionary a plurality of times. FIG. 4 illustrates the retrieval processing of concept network connection information to be performed in the conventional concept management device. Incidentally, in this figure, each graph (namely, each network of nodes connected by arrows) represents a concept network connection. Further, each node designates a word represented by a Japanese character , , . . . or .
Thus, in case of the conventional device, the addition of information to the concept network connection information held in the fundamental dictionary data holding portion 51 can be effected by using the supplemental concept network connection information held in the field concept dictionary data holding portion 52 and the personal concept dictionary data holding portion 54. Consequently, an environment, in which a concept expansion is performed on the input word (namely, the network corresponding to the input word (hereunder sometimes referred to as the concept range of the input word) is expanded), can be provided to each user. However, in case of the conventional device, the concept network connection information corresponding to an input word, which is held in the fundamental concept dictionary data holding portion 51, cannot be reduced. Thus, an environment in which the concept range of the input word is reduced, cannot be provided to each user. This is disadvantageous when concept expansion is performed on a key word used for full text retrieval by using the concept dictionary. Further, an unnecessary concept expansion performed on the key word results in retrieval of unnecessary information or documents.
The present invention is accomplished to eliminate the above described drawback of the conventional device.
It is, therefore, an object of the present invention to provide a concept dictionary management device which can expand and reduce concept network connection information held in a fundamental concept dictionary data holding portion used in common by a plurality of users without rewriting the concept network connection information thereby performing full text retrieval at a high speed.